MDKSA-2005:200

Problem description

The mod_auth_shadow module 1.0 through 1.5 and 2.0 for Apache with
AuthShadow enabled uses shadow authentication for all locations that
use the require group directive, even when other authentication
mechanisms are specified, which might allow remote authenticated users
to bypass security restrictions.

This update requires an explicit "AuthShadow on" statement if website
authentication should be checked against /etc/shadow.